The present invention relates to an in-vehicle device that displays a plurality of screen data generated by a mobile terminal device carried by a passenger on one display and a display control system including such an in-vehicle device, and more particularly, to an in-vehicle device and a display control system capable of providing a plurality of screen data for a passenger to grasp the screen data easily in a type suitable for in-vehicle circumstances.
Recently, as ear navigators providing route information to a destination have come into wide use, vehicles have been generally provided with display devices such as liquid crystal displays. In addition, mobile terminal devices such as mobile phones and PDAs (Personal Digital Assistant) have come into wide use, and screen data generated by the mobile terminal devices have been displayed on the display devices built into vehicles.
When the plurality of screen data generated by one mobile terminal device or the plurality of screen data generated by a plurality of mobile terminal devices are displayed on one display device, it is necessary to perform screen control to adjust display positions or display sizes of the screen data due to a limit of a display area of the display device. As a method of such screen control, there is a method of displaying superimposed windows corresponding to the screen data and changing positions of the windows or display order by operation of a mouse or a keyboard, which is widely used in the field of personal computers.
In a method disclosed in Patent Document 1, when a navigation screen and screens generated by a mobile phone are displayed on an in-vehicle display device, priority of positions, sizes and display orders are specified, and a window with high priority is displayed on the front side when the windows are superimposed.
Patent Document 1: Japanese Patent Publication No. 2001-014133 A
However, the screen control method used in the field of personal computers assumes the operation of a mouse or keyboard, and there is a problem in that it is difficult to perform delicate window operations in a vehicle subject to vibration. The technique of Patent Document 1 assumes that the superimposed windows are displayed and controlled, but there is also a problem in that it is difficult to pick up a desired window from the superimposed windows in the vehicle where it is difficult to perform the window operations.
In the above-described background art, a new window can be opened and the positions or the display order of the windows can be freely changed. Accordingly, the screen layout on the display device may be drastically changed by a slight mistake in operation. However, when the former window is drastically changed in in-vehicle circumstances where there is little chance of constantly looking at the display device, it is difficult to grasp the displayed contents immediately.
Arising from these points, there is a chief difficulty as to how to realize an in-vehicle device or a display control system even in in-vehicle circumstances where it is difficult to perform the screen operations due to vibration or the like and it is necessary to grasp immediately information displayed on the display device.